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Article
Constructing a New Exponentiated Family Distribution with Reliability Estimation

Author: Shurooq A. K. Al-Sultany
Journal: Al-Mustansiriyah Journal of Science مجلة علوم المستنصرية ISSN: 1814635X Year: 2018 Volume: 29 Issue: 2 Pages: 155-163
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

This paper deals with using one method for transforming two parameters given distribution to another form with three parameters distribution, through using idea of reparameterization with powering the given cumulative distribution function by new parameter, where this work gives a new family through using new parameter which is necessary for generating values of the r.v from given CDF through smoothing the values of the given random variable to obtain new values of r.v using three sets of parameters rather than two. The new model Frechet p.d.f is obtained and also its Cumulative distribution function is found then we apply three methods of estimation (Maximum likelihood, moments estimator and the third method (is nonlinear least square. Different set of initial values of parameters ( , , ) and different samples Size (n=25,50,75,100) was used. The simulation procedure is done using matlab-R2014b, and results are compared using integrated Mean square error.

يتناول هذا البحث استخدام الطريقة الاولى لتحويل معلمتين لتوزيع معطى الى شكل توزيع اخر بثلاث معالم من خلال استخدام فكرة اعادة التشكيل وذلك برفع دالة التوزيع التراكمية للتوزيع المعطى لقوى بواسطة معلمة جديدة, حيث يعطي هذا العمل عائلة جديدة من خلال استخدام معلمة جديدة وهو أمر ضروري لتوليد قيم المتغير العشوائي من دالة توزيع تراكمية معينة من خلال صقل قيم المتغير العشوائي نظرا إلى الحصول على قيم جديدة من المتغير العشوائي باستخدام ثلاثة مجموعات من المعلمات بدلا من اثنين. الانموذج الجديد الذي تم الحصول عليه هو دالة كثافة احتمال فريشيت كما تم الحصول على دالة التوزيع التراكمي ومن ثم تطبيق ثلاث طرائق للتقدير (والتي هي الامكان الاعظم، مقدر العزوم، والطريقة الثالثة تعتمد على استخدام طريقة انحدار المربعات الصغرى). تم اختيار مجموعة مختلفة من القيم الابتدائية للمعالم ( , , )بأحجام عينات مختلفة (n=25,50,75,100). تم إجراء المحاكاة باستخدام ماتلاب-R2014b، وتمت مقارنة النتائج باستخدام متوسط مربعات الخطا التكاملي.


Article
The Weighted Transmuted Pareto Distribution

Author: Kareema Abed Al-kadim and Maysaa Hameed Mohammed
Journal: Albahir journal مجلة الباهر ISSN: 23125721 Year: 2018 Volume: 7 Issue: 13-14 Pages: 73-81
Publisher: Shiite Endowment ديوان الوقف الشيعي

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Abstract

The lifetime distributions play important role in many real life fields such as the biostatistics, reliability and survival analysis, so we try to contribute infinding anew proposed lifetime distribution, weighted transmuted Pareto distribution, and discuss some of its statistical properties.

ان ﺗﻮزﻳﻊ اﳊﻴﺎة ﻳﻠﻌﺐ دورا ﻣﻬﲈ ﰲ ﳎﺎﻻت اﳊﻴﺎة اﳌﺨﺘﻠﻔﻪ ﻛﺎﻷﺣﺼﺎءات اﳊﻴﺎﺗﻴﺔ، ﲢﻠﻴﻞ اﳌﻌﻮﻟﻴﺔ او اﻟﺒﻘﺎء،... اﻟﺦ. وﰲ ﻫﺬا اﻟﺒﺤﺚ ﺣﺎوﻟﻨﺎ اﳌﺴﺎﳘﺔ ﰲ اﳚﺎد ﺗﻮزﻳﻊ ﺣﻴﺎة ﻣﻘﱰح وﻫﻮ ﺗﻮزﻳﻊ ﺑﺎرﻳﺘﻮ اﳌﺤﻮل اﳌﻮزون ﻣﻊ ﻣﻨﺎﻗﺸﺔ ﺑﻌﺾ اﳋﻮاص.


Article
PAPR Reduction in Coherent Optical OFDM System using Modified Sliding Norm Transformer

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Abstract

Orthogonal Frequency Division Multiplexing is one of the mostimportant multiple carrier modulation format, which has many applications inwireless communication and optical communication. It is considered as anexcellent method for fast optical communication inferable from its high spectralefficiency and its strength to path losses. Peak to average power ratio isregarded as one of the main problems that are experienced by the opticalorthogonal frequency division multiplexing system, which directly affects thecharacteristics of the system. The current paper proposes an efficient techniqueto reduce Peak to Average Power Ratio by the modified Dursun’s method or theso called modified discrete sliding norm transformer in coherent opticalorthogonal frequency division multiplexing system for the first time to the baseof our knowledge consequently. The proposed technique does not need to sendside information to the receiver; also, it does not degrade bandwidth. Thisalgorithm lessens Peak to Average Power Ratio in the optical coherentOrthogonal Frequency Division Multiplexing system to about 4.15 dB atcomplementary cumulative distribution function (CCDF) probability of 10-3 andimproves the system performance.


Article
Mitigate PAPR Effect in Optical Orthogonal Frequency Division Multiplexing Using Companding Technique

Authors: Mohammed A. Husein --- Sinan M. Abdul Satar --- Ali n. Kareem
Journal: IRAQI JOURNAL OF COMPUTERS,COMMUNICATION AND CONTROL & SYSTEMS ENGINEERING المجلة العراقية لهندسة الحاسبات والاتصالات والسيطرة والنظم ISSN: 18119212 Year: 2018 Volume: 18 Issue: 3 Pages: 60-69
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

orthogonal frequency division multiplexing (OFDM) is emerging asthe leading technology for high data rates. The OFDM based on multicarriertransmission that transforms a wideband channel into a group of thin-bandchannels. The high peak to average power ratio (PAPR) considers the maindrawback factor in this system, so the companding technique modifies theamplitude of OFDM signal to reduce this factor. The proposed A-lawcompanding technique has been implemented in intensity modulation/directdetection optical orthogonal frequency division multiplexing (IM/DDOOFDM).The proposed companding scheme guarantees the improvedperformance in terms of bit error rate (BER) and quality factor (QF) whilereducing PAPR effectively and efficiently by modifying the amplitude of thetransmitted signals. Our results confirm that the suggested scheme exhibits agood ability to reduce PAPR and a good BER performance based on the use theA factor. At the complementary cumulative distribution function (CCDF) of 10-3, the PAPR value of our proposed scheme is about 4.4 dB lower than those ofun-companded signal at best control factor used of A at 87.6, accordingly theQF is 2.5 dB and the BER is 6.2×10-3 at a distance 900km without anyequalization technique or training sequence or any channel estimation.


Article
Compare some estimation methods for parameters of extreme value distribution by simulation
مقارنة بعض طرق التقدير لمعلمات توزيع القيم المتطرفة باعتماد المحاكاة

Author: أ.م.د.وليد عبدا لله ارحيمه أ.م.د. نزار مصطفى الصراف
Journal: Al Kut Journal of Economics Administrative Sciences مجلة الكوت للعلوم الاقتصادية والادارية ISSN: 1999558X Year: 2012 Volume: 1 الجزء الثاني Issue: عدد خاص بالمؤتمر العلمي Pages: 287-302
Publisher: Wassit University جامعة واسط

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Abstract

AbstractResearch has included study of extreme value distribution properties with most important functions which it is used in some estimation methods for the parameters distribution also research include simulation experiments with various sample sizes and parameters values using mean square error to determined the best estimation method

الخلاصة(Abstract ) تضمن البحث دراسة خواص توزيع القيم المتطرفة مع أهم الدوال ألعائده له تمهيدا لاستخدام هذه الدوال في تقديم بعض طرائق التقدير لمعلمات هذا التوزيع مع تقديم تجارب محاكاة لعدة احجام وعدة اقيام لمعلمات التوزيع في محاولة لتوظيف متوسط مربعات الخطأ لمعرفة تحرك المقدرات المقدمة وفق هذه الطرق وتحديد طريقة التقدير الأفضل من بين الطرق المدروسة

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